کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1716057 1519986 2011 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Decrease of contractile properties and transversal stiffness of single fibers in human soleus after 7-day “dry” immersion
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی هوافضا
پیش نمایش صفحه اول مقاله
Decrease of contractile properties and transversal stiffness of single fibers in human soleus after 7-day “dry” immersion
چکیده انگلیسی
The simulation model of “dry” immersion was used to evaluate the effects of plantar mechanical stimulation (PMS) and high frequency electromyostimulation (EMS) on the mechanical properties of human soleus fibers under the conditions of gravitational unloading. We examined contractile properties of single fibers by means of tensometry, transversal stiffness of sarcolemma and different areas of the contractile apparatus by means of atomic force microscopy. It was shown that there is a reduction of transversal stiffness in single muscle fibers under hypogravitational conditions. Application of different countermeasures could compensate this effect. Meanwhile pneumostimulation and electro stimulation act in quite different way. Therefore, pneumostimulation seems to be more effective. The data obtained can be considered as the evidence of the fact that such countermeasures as PMS and electromyostimulation influence on muscle fibers in quite different ways and PMS efficiency is likely to be higher. On the basis of our experimental data on transverse stiffness of mechanotransductional nodes and the contractile apparatus, we can assume that support stimulation allows prevention of destructive processes in muscle fibers. Electrostimulation seems to stimulate contractile activity only without suppression of impairment of the fiber mechanical properties.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Acta Astronautica - Volume 68, Issues 9–10, May–June 2011, Pages 1478-1485
نویسندگان
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